The present invention relates to a method of blocking blood flow toward a target tissue such as cancerous tissue and a warming apparatus suitable for conducting the method, and more particularly, the invention relates to a blood flow blocking method and a warming apparatus for injecting into a blood flow system of a living body microballoons each having a shell made of a thermoplastic material and having a pressurized gas encapsulated within the shell, expanding the microballoons by increasing the temperature of the localized target tissue, and selectively blocking the blood flow of the body by choking capillary vessels with the expanded microballoons.
Examples of non-invasive therapy of cancer include a procedure wherein blood flow in blood vessels through which cancerous cells are nourished are blocked to necrotize the cancerous cells within a relatively short term.
A variety of techniques for blocking blood flow exist. Although these techniques are preferred rather than a technique which momentarily cauterizes the cancerous cells or a technique which slowly inhibits regeneration of the cancerous cells such as hyperthermia, a need is felt for an intermediate technique, like the techniques for blocking blood flow, which, in addition, allows a physician to instantly ascertain the result.